Antigenic iron repressible proteins from N. meningitidis related to the hemolysin family of toxins

ABSTRACT

An isolated, antigenic polypeptide comprises a segment having at least fifty amino acid residues. The amino acid sequence of the segment is present in  N. meningitidis,  and is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins.

[0001] This application is a continuation-in-part of Ser. No. 07/895,123 filed Jun. 8, 1992, which is incorporated herein by reference.

[0002] The present invention is directed to antigenic polypeptides isolated from Neisseria meningitidis, antibodies raised against the polypeptides, vaccines containing the polypeptides and DNA encoding the polypeptides. The polypeptides are members of the hemolysin family of toxins, a typical member of which is alpha-hemolysin from E. coli.

[0003] Bacterial pathogenesis is a complicated and often poorly understood process. Many pathogenic bacteria secrete toxins that impair the metabolism and function of animal cells. Various classes of molecules constitute such toxins.

[0004] An example of a protein toxin is found in pathogenic E. coli strains that cause extra-intestinal infections in humans. Such infections are characterized by the lysis of mammalian erythrocytes. The hemolytic activity is due to a class of toxins known as hemolysin. The class includes alpha-hemolysin and beta-hemolysin; see Welch et al, Infection and Immunity 42, 178-186 (1983).

[0005] Another protein toxin is adenylate cyclase, which is found in Bordetella pertussis and Bacillus anthracis, and which impairs functions of professional phagocytes. These bacteria are responsible for whooping cough and anthrax, respectively.

[0006] A third class of protein toxins from pathogenic bacteria are the leukotoxins, which are found in Actinobacillus actinomycetemcomitans, which is the etiologic agent of localized juvenile periodontitis, and Pasteurella haemolytica, which kills bovine leukocytes.

[0007] Interestingly, the adenylate cyclase from B. pertussis and B. anthracis and the leukotoxins from A. actinomycetemcomitans and P. haemolytica have amino acid sequences that exhibit considerable homology with that of alpha-hemolysin from E. coli; see Glaser et al, Molecular Biology 2, 19-30 (1988) and Kolodrubetz et al, Infection and Immunity 57, 1465-1469 (1989). Apparently, there is a class of toxins found in various genera of bacteria. The amino acid sequence of this family of cytotoxins is characterized by a highly repeated nine amino acid motif, LxGGxGNDx, wherein x represents any amino acid. For the purposes of this specification, this family of toxins will be referred to as the hemolysin family of toxins.

[0008] It should be understood that “hemolysin family of toxins” is a generic name familiar to those in the art, and is not meant to imply that all members are hemolytic, or, for that matter, cytotoxic, although most are. Membership in the family depends on the existence of homology in the amino acid sequence, as defined below. In addition to those mentioned above, homologous proteins have also been found in Serratia and Proteus, although it is not certain whether these members of the hemolysin family are, in fact, cytotoxic.

[0009] Little is known about the intriguing and sometimes fatal bacteria Neisseria meningitidis, which is responsible for spinal meningitis and septic shock. N. meningitidis and the diseases it causes have been reviewed by Paterson in “Neisseria meningitidis and Meningococcal Disease” in Biologic and Clinical Basis of Infectious Diseases, W. B. Saunders Company, Chapter 43 (1980).

[0010] The genotype of N. meningitidis is very similar to that of N. gonorrhoeae, although the phenotype is quite different. It is often important to distinguish between these Neisseria species. Immunologic speciation is often difficult due to a lack of sufficient amounts of group-specific antigens.

[0011]N. meningitidis exists as various serotypes, the prevalence of which varies with time and location. The serotypes include A, B, C, D, X, Y, Z, 29-E and W-135.

[0012] The three most important known antigenic and/or toxic constituents of N. meningitidis infections are a capsular polysaccharide, a lipopolysaccharide-endotoxin cell wall complex and a Neisseria-specific protein. The capsular polysaccharide is a major virulence factor that enables meningococci to resist phagocytosis by segmented neutrophils.

[0013] Vaccines containing meningococcal polysaccharides are used against some of the serotypes of N. meningitidis. For example, protection against the A, C, Y and W-135 serotypes is afforded by polysaccharide vaccines. Such vaccines are, however, inadequate for general protection against infection against N. meningitidis. For example, the immune response of serotypes A and C to polysaccharide vaccines is poor, especially in children under two years old, who constitute the group most susceptible to meningococcal disease. Moreover, no effective vaccine exists for serotype B, possibly because the group B capsular polysaccharide is relatively non-immunogenic.

[0014] It is apparent that much needs to be learned about the pathology of N. meningitidis. Possibly, additional understanding of this pathogen will lead to the discovery of useful vaccines in general for more serotypes than are currently available.

[0015] For example, it is not known why the colonization of the respiratory tract by N. meningitidis progresses to acute meningococcal disease and sometimes death in an occasional individual, whereas it does not do so in the great majority of others who are apparently at comparable risk. The amount of neither capsular polysaccharide nor lipopolysaccharide-endotoxin complex correlates with the seriousness of this disease. Exposure to microorganisms with antigenic constituents that cross-react with capsular polysaccharides of N. meningitidis has been proposed as an explanation; see Paterson, id.

[0016] Other explanations are also possible. For example, cross-immunity to antigens other than capsular polysaccharides cannot be ruled out. It is interesting to note in this regard that there are no known protein toxins associated with N. meningitidis. One reason for this may be that N. meningitidis is often cultured in vitro under iron-rich conditions that do not exist in a human host. It is known, however, that some meningococcal proteins are iron-repressed and are not observed in vitro, although they are expressed in vivo. See Black et al., Infection and Immunity 54, 710-713 (1986) and Brener et al, ibid. 33, 59-66 (1981).

[0017] One problem addressed by the present invention is the discovery of antigenic polypeptides and DNA sequences that are capable of identifying N. meningitidis and distinguishing it from N. gonorrhoeae. Another problem addressed by the present invention is the discovery of proteins capable of producing antibodies effective against meningococcal disease.

SUMMARY OF THE INVENTION

[0018] These and other problems as will be apparent to those having ordinary skill in the art have been solved by providing an isolated, antigenic polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is present in N. meningitidis, and wherein the amino acid sequence is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins.

[0019] Another way of defining the polypeptide is to say that it is an isolated polypeptide comprising a segment having an amino acid sequence present in N. meningitidis wherein the amino acid sequence consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of:

[0020] L at position 1;

[0021] G at position 3;

[0022] G at position 4;

[0023] G at position 6;

[0024] N at position 7;

[0025] D at position 8; and

[0026] x at positions 2, 5 and 9;

[0027] wherein x, independently, represents any single amino acid residue.

[0028] The invention further includes antigenic fragments of such polypeptides, antibodies raised against such polypeptides, nucleotide sequences encoding such polypeptides, and vaccines containing such polypeptides.

BRIEF DESCRIPTION OF THE FIGURES

[0029]FIG. 1 shows the DNA and amino acid sequence of the gene for an antigenic iron repressible protein (frpA) from N. meningitidis related to the hemolysin family of toxins. See Seq. ID No. 1.

[0030]FIG. 2 shows the putative amino acid sequence for the DNA sequence of FIG. 1. See Seq. ID No. 2.

DETAILED DESCRIPTION OF THE INVENTION The Polypeptide Segment

[0031] It has unexpectedly been discovered that when N. meningitidis is grown under iron-limiting conditions, a polypeptide comprising a segment having an amino acid sequence that is different from, but substantially homologous with, a segment of the hemolysin family of toxins is expressed. Monoclonal antibodies raised against the polypeptide found in N. meningitidis, such as A4.85 (see below), cross-react in Western blots with alpha-hemolysin (HlyA) produced by the hlyA gene in E. coli and adenylate cyclase produced in Bordetella pertussis.

[0032] The hemolysin family of toxins, as used herein, includes the homologous, cytotoxic or proteolytic polypeptides found in bacteria of the genera Escherichia, Serratia, Pasteurella, Proteus, Actinobacillus, and Bordetella. The family specifically includes alpha-hemolysin, leukotoxin, and adenylate cyclase.

[0033] Determinations whether two amino acid sequences are substantially homologous are, for the purpose of the present specification, based on FASTA searches in accordance with Pearson and Lipman, Proc. Natl. Acad. Sci. USA 85, 2444-2448 (1988). A substantially homologous sequence in accordance with the present invention has at least 15% identity, preferably at least 20% identity and, more preferably, at least 25% identity in amino acid sequence when determined in accordance with the method of Pearson and Lipman, which is incorporated herein by reference.

[0034] The polypeptide of the present invention need not contain a segment that is identical to other members of the hemolysin family of toxins. The identity in accordance with the FASTA method may be as high as 90% or 95%, but when isolated from N. meningitidis normally does not exhibit identities greater than 40% or 50%.

[0035] The size of the polypeptide is not critical, as long as it contains a segment that is substantially homologous to a segment of a member of the hemolysin family of toxins. The substantially homologous segment has at least fifty amino acid residues, preferably at least 100 amino acid residues, and more preferably at least 200 amino acid residues. In this specification, the word “polypeptide” will be considered indistinguishable from words like “protein” and “peptide.”

[0036] The segment of the meningococcal polypeptide that is substantially homologous to a segment of the hemolysin family of toxins contains the same nine amino acid motif that is characteristic of all the members of the hemolysin family of toxins. The consensus sequence is LxGGxGNDx, hereinafter hemolysin consensus sequence. The amino acid represented by x may be any single amino acid.

[0037] The polypeptide of the invention may be defined in terms of the hemolysin consensus sequence as well as by the substantial homology standard described above. For this purpose, a nine amino acid sequence is considered to be a hemolysin consensus sequence if it contains at least four, preferably at least five, and more preferably all six of the specifically defined amino acid residues (i.e. L-GG-GND-) at the correct position.

[0038] Referring to FIG. 2, which, as described below, is a polypeptide isolated from N. meningitidis, the homologous segment comprises two stretches of multiple repeats of the hemolysin consensus sequence, i.e. between amino acids 763 and 789; between amino acids 900 and 989. There are 13 complete consensus sequences in FIG. 2. See Seq. ID No. 2.

[0039] The polypeptides of the present invention contain segments that are present in N. meningitidis and that comprise at least three, preferably at least five, and more preferably at least ten hemolysin consensus sequences. The polypeptides of the invention may have as many as at least 21 hemolysin consensus sequences.

[0040] The polypeptide is isolated, which means that it is essentially free of other proteins, especially of other proteins from N. meningitidis. Essentially free from other proteins means that it is at least 90%, preferably at least 95% and, more preferably, at least 98% free of other proteins.

[0041] Preferably, the polypeptide is essentially pure, which means that the polypeptide is free not only of other polypeptides, but also of other materials used in the isolation and identification of the polypeptide, such as, for example, sodium dodecyl sulfate and other detergents as well as nitrocellulose paper. The polypeptide is at least 90% free, preferably at least 95% free and, more preferably, at least 98% free of such materials.

[0042] The polypeptide of the present invention is antigenic, which means that the polypeptide induces specific antibodies in a mammal. Preferably, the polypeptide is immunogenic.

[0043] The polypeptide may be the entire polypeptide as it exists in N. meningitidis, or an antigenic, preferably immunogenic, fragment of the whole polypeptide. Antigenic and/or immunogenic fragments of antigenic and/or immunogenic polypeptides may be identified by methods known in the art. Usually, the antigenic fragment will comprise at least a portion of the segment having an amino acid sequence that is different from, but homologous, to the amino acid sequence of a segment of a polypeptide that is a member of the hemolysin family of toxins, or will comprise at least a portion of the segment having at least three, preferably at least five, and more preferably at least ten hemolysin consensus sequences.

Preparation of the Polypeptide

[0044] The polypeptides of the present invention may be prepared by methods known in the art. Such methods include isolating the polypeptide directly from N. meningitidis; isolating or synthesizing DNA encoding the polypeptide and using the DNA to produce recombinant polypeptide; and synthesizing the polypeptide from individual amino acids.

[0045] The polypeptide or DNA encoding the polypeptide may be isolated from any serotype of N. meningitidis. Such serotypes include A, B, C, D, X, Y, Z, 29-E and W-135.

[0046] Suitable sources of meningococcal strains from which the polypeptide and DNA encoding the polypeptide may be isolated are available. Such sources include the American Type Culture Collection (Bethesda, Md.) and the Neisseria Repository (NAMRU, University of California, Berkeley). Suitable strains include FAM18 and FAM20 (Dyer et al, Microbial Pathogenesis 3, 351-363 (1987)), and FAM 19. Additional meningococcal strains are described by Schryvers and Morris in Infection and Immunity 56, 1144-1149 (1988).

[0047] The polypeptide may be isolated directly from N. meningitidis by methods known in the art. First, meningococcal outer membranes are isolated and prepared by known methods. The methods described by West and Sparling in Infect. Immun. 47, 388-394 (1985) and by Schryvers and Morris in Infect. Immun. 56, 1144-1149 (1988) are suitable.

[0048] The isolated membrane proteins may be solubilized by known methods, such as the addition of detergents. Commonly used detergents include Octyl-B-Glucoside, Chaps, Zwittergent 3.14 or Triton-X. The use of detergents to enhance solubility of membrane proteins is described by Jones et al. in Finby, Solubilization and Reconstitution of Membrane Proteins: A Practical Approach, IRL Press (1986), Helenius et al. in Biochim. Biophys. Acta 415, 29 (1975) and Hjelmeland and Chrambach, Methods Enzymol. 104, 305 (1984).

[0049] Proteins are isolated from the solubilized membrane fraction by standard methods. Some suitable methods include precipitation and liquid chromatographic protocols such as ion exchange, hydrophobic interaction and gel filtration. See, for example, Methods Enzymol. 182 (Guide to Protein Chemistry, Deutscher, Ed. Section VII) 309 (1990) and Scopes, Protein Purification. Springer-Verlag, New York (1987).

[0050] Alternatively, purified material is obtained by separating the protein on preparative SDS-PAGE gels, slicing out the band of interest and electroeluting the protein from the polyacrylamide matrix by methods known in the art. The detergent SDS is removed from the protein by known methods, such as by dialysis or the use of a suitable column, such as the Extracti-Gel column from Pierce.

[0051] The polypeptide may also be produced by isolating DNA that encodes the polypeptide; cloning the DNA in a suitable host; expressing the DNA in the host; and harvesting the polypeptide.

[0052] The first DNA encoding the polypeptide of the present invention was isolated by an immunoscreening method. Such methods are described by Maniatis et al in “Molecular Cloning: A Laboratory Manual,” Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1982).

[0053] Briefly, monoclonal antibodies were generated against iron-stressed outer membrane proteins of N. meningitidis strain FAM20. One monoclonal antibody, A4.85, recognized several iron-regulated proteins in Western blots of the FAM20 outer membranes. A4.85 was used to isolate a clone from an FAM20 genomic library constructed in the expression vector lambda-gt11. The sequence of this clone was determined and used to clone adjacent genomic restriction fragments. The adjoined DNA sequence of this region contained a long open reading frame, which is included in FIG. 1. See Seq. ID No. 1. The amino acid sequence predicted from the nucleotide sequence of FIG. 1 is shown as FIG. 2. See Seq. ID No. 2.

[0054] A FASTA homology search in accordance with Pearson and Lipman, Proc. Natl. Acad. Sci. USA 85, 2444-2448 (1988) of the amino acid sequence deduced from the open reading frame (FIG. 2) was performed. Surprisingly, the amino acid sequence exhibited substantial homology to several members of the hemolysin family of toxins, as discussed above.

[0055] As further evidence that the polypeptide isolated from N. meningitidis is a member of the hemolysin family of toxins, the antibody raised against, and used to isolate, the polypeptide shown as FIG. 2 (See Seq. ID No. 2.), A4.85, cross-reacted strongly with alpha-hemolysin (HlyA) from E. coli and with adenylate cyclase produced in Bordetella pertussis.

[0056] The immunoscreening method may be repeated in order to obtain additional fragments of the gene encoding the polypeptide of the invention or to obtain the gene encoding the entire polypeptide. It is, of course, not necessary to repeat the immunoscreening process. The entire gene or additional fragments of the gene are preferably isolated by using the known DNA sequence or fragments thereof as a probe. To do so, meningococcal DNA restriction fragments, either flanking the ends of the region already cloned or containing the entire region, are identified by Southern hybridization using labelled oligonucleotide probes derived from a previously determined sequence, such as that shown as FIG. 1, or a fragment thereof. See Seq. ID No. 1.

[0057] The DNA obtained may be amplified by methods known in the art. One suitable method is the polymerase chain reaction (PCR) method described by Mullis et al in U.S. Pat. No. 4,683,195 and by Sambrook, Fritsch and Maniatis (eds) in Molecular Cloning, A Laboratory Manual, Second Edition, Cold Spring Harbor Laboratory Press (1989). It is convenient to amplify the clones in the lambda-gt11 vectors using lambda-gt11-specific oligomers as the amplimers (available from New England Biolabs, Beverly, Mass.).

[0058] The restriction fragments are cloned into a suitable vector, such as a plasmid or bacteriophage, and sequenced in accordance with methods known in the art. A suitable sequencing method is the dideoxy chain terminating method described by Sanger et al in Proc. Natl. Acad. Sci. USA 74, 5463-5467 (1977). Suitable vectors and polymerases for sequencing are known. A suitable vector is the lambda-gt11 specific primer. (New England Biolabs, Beverly, Mass.). A suitable polymerase is Sequenase (United States Biochemical Corp., Cleveland, Ohio).

[0059] The DNA encoding the polypeptide of the invention may be used to express recombinant polypeptide in a wide variety of host cells using a wide variety of vectors. The host may be prokaryotic or eukaryotic. The DNA may be obtained from natural sources and, optionally, modified. The genes may also be synthesized in whole or in part.

[0060] Cloning vectors may comprise segments of chromosomal, non-chromosomal and synthetic DNA sequences. Some suitable prokaryotic vectors include plasmids from E. coli, such as colE1, pCR1, pBR322, pMB9, and RP4. Prokaryotic vectors also include derivatives of phage DNA such as M13, f1, and other filamentous single-stranded DNA phages.

[0061] Vectors for expressing proteins in bacteria, especially E. coli, are also known. Such vectors include pK233 (or any of the tac family of plasmids), T7, and lambda P_(L). Examples of vectors that express fusion proteins include the PATH vectors described by Dieckmann and Tzagoloff in J. Biol. Chem. 260, 1513-1520 (1985). These vectors contain DNA sequences that encode anthranilate synthetase (TrpE) followed by a polylinker at the carboxy terminus. Other expression vector systems are based on beta-galactosidase (pEX); maltose binding protein (pMAL); and glutathione S-transferase (PGST)—see Gene 67, 31 (1988) and Peptide Research 3, 167 (1990).

[0062] Vectors useful in yeast are available. A suitable example is the 2μ plasmid.

[0063] Suitable vectors for use in mammalian cells are also known. Such vectors include well-known derivatives of SV-40, adenovirus, retrovirus-derived DNA sequences and vectors derived from combination of plasmids and phage DNA.

[0064] Further eukaryotic expression vectors are known in the art (e.g., P. J. Southern and P. Berg, J. Mol. Appl. Genet. 1, 327-341 (1982); S. Subramani et al, Mol. Cell. Biol. 1, 854-864 (1981); R. J. Kaufmann and P. A. Sharp, “Amplification And Expression Of Sequences Cotransfected with A Modular Dihydrofolate Reductase Complementary DNA Gene,” J. Mol. Biol. 159, 601-621 (1982); R. J. Kaufmann and P. A. Sharp, Mol. Cell. Biol. 159, 601-664 (1982); S. I. Scahill et al, “Expression And Characterization Of The Product Of A Human Immune Interferon DNA Gene In Chinese Hamster Ovary Cells,” Proc. Natl. Acad. Sci. USA 80, 4654-4659 (1983); G. Urlaub and L. A. Chasin, Proc. Natl. Acad. Sci. USA 77, 4216-4220, (1980).

[0065] Useful expression hosts include well-known prokaryotic and eukaryotic cells. Some suitable prokaryotic hosts include, for example, E. coli, such as E. coli SG-936, E. coli HB 101, E. coli W3110, E. coli X1776, E. coli X2282, E. coli DHI, and E. coli MRCl, Pseudomonas, Bacillus, such as Bacillus subtilis, and Streptomyces. Suitable eukaryotic cells include yeasts and other fungi, insect, animal cells, such as COS cells and CHO cells, human cells and plant cells in tissue culture.

[0066] The expression vectors useful in the present invention contain at least one expression control sequence that is operatively linked to the DNA sequence or fragment to be expressed. The control sequence is inserted in the vector in order to control and to regulate the expression of the cloned DNA sequence. Examples of useful expression control sequences are the lac system, the trp system, the tac system, the trc system, major operator and promoter regions of phage lambda, the control region of f1 coat protein, the glycolytic promoters of yeast, e.g., the promoter for 3-phosphoglycerate kinase, the promoters of yeast acid phosphatase, e.g., Pho5, the promoters of the yeast alpha-mating factors, and promoters derived from polyoma, adenovirus, retrovirus, and simian virus, e.g., the early and late promoters or SV40, and other sequences known to control the expression of genes of prokaryotic or eukaryotic cells and their viruses or combinations thereof.

[0067] The recombinant polypeptide is purified by methods known in the art. Suitable methods are described F. A. O. Marston, “The Purification of Eukaryotic Polypeptides Expressed in Escherichia coli,” in DNA Cloning, D. M. Glover, Ed., Vol. III, IRL Press Limited, England (1987).

[0068] The polypeptide of the invention and DNA encoding the polypeptide may also be chemically synthesized from individual amino acid residues and nucleotides, respectively, by methods known in the art. Suitable methods for synthesizing the polypeptide are described by Stuart and Young in “Solid Phase Peptide Synthesis,” Second Edition, Pierce Chemical Company (1984). Suitable methods for synthesizing DNA are described by Caruthers in Science 230, 281-285 (1985).

Vaccines

[0069] A polypeptide comprising a segment having an amino acid sequence that is different from, but substantially homologous with, the amino acid sequence of a member of the hemolysin family of toxins is, unexpectedly, an antigen useful for protecting a mammal from infectious diseases caused by N. meningitidis. The mammal is typically a human.

[0070] To be useful, the antigen is non-toxic to the mammal being immunized. If the antigen is toxic, it may be detoxified by methods known in the art. Such methods include, for example, providing antigenic, non-toxic fragments of the entire polypeptide or detoxifying a polypeptide by, for example, binding the toxin to a carrier molecule that destroys toxicity, but does not affect antigenicity. The carrier molecule is typically another polypeptide.

[0071] Preferably, an amino acid sequence of the antigen is present in a polypeptide found in N. meningitidis. The polypeptide or non-toxic, antigenic fragments useful in immunizing mammals may be made by methods known in the art, such as by isolation from N. meningitidis, production by recombinant DNA techniques, or chemical synthesis, as described above.

[0072] The length of the fragment is not critical as long as the fragment is antigenic and non-toxic. Therefore, the fragment should contain sufficient amino acid residues to define the epitope. Methods for isolating and identifying antigenic fragments from known antigenic polypeptides are described by Salfeld et al. in J. Virol. 63, 798-808 (1989) and by Isola et al. in J. Virol. 63, 2325-2334 (1989).

[0073] If the fragment defines the epitope, but is too short to be antigenic, it may be conjugated to a carrier molecule. Some suitable carrier molecules include keyhole limpet hemocyanin and bovine serum albumen. Conjugation may be carried out by methods known in the art. One such method is to combine a cysteine residue of the fragment with a cysteine residue on the carrier molecule.

[0074] The present invention further includes vaccine compositions for immunizing mammals, including humans, against infection by N. meningitidis. The vaccine comprises an immunogenic antigen as described above in a suitable carrier. Suitable carriers include any of the standard pharmaceutically acceptable carriers, such as water, phosphate buffered saline solution, and emulsions.

[0075] The vaccine may include adjuvants, such as muramyl peptides, and lymphokines, such as interferon, interleukin-1 and interleukin-6. The antigen may be adsorbed on suitable particles, such as aluminum oxide particles, or encapsulated in liposomes, as is known in the art.

[0076] The invention further includes methods of immunizing host mammals, including humans, by administering the vaccine compositions described above to mammals in need of protection from diseases caused by N. meningitidis. The vaccine comprises an immunogenic polypeptide in a form that is non-toxic to mammals. The polypeptide comprises an amino acid sequence that is homologous with the amino acid sequence of a member of the hemolysin family of toxins. The amino acid sequence is preferably present in N. meningitidis, and is usually found in the outer membranes of N. meningitidis. Since, however, antibodies cross-react with the polypeptide of the invention and members of the hemolysin family of toxins from other genera of bacteria, the antigen in the vaccine composition may comprise an amino acid sequence in such other genera, such as from E. coli or B. pertussis.

[0077] The vaccine may be administered to a mammal by methods known in the art. Such methods include, for example, intravenous, intraperitoneal, subcutaneous, or intramuscular administration.

Antibodies

[0078] The present invention provides antibodies raised against a polypeptide of the invention. The polypeptide comprises an amino acid sequence that defines an epitope, and is substantially homologous with the amino acid sequence of a member of the hemolysin family of toxins. The antibodies are preferably raised against a polypeptide comprising an amino acid sequence that is present in N. meningitidis, and that is different from polypeptides that are members of the hemolysin family of toxins from other genera of bacteria.

[0079] The antibodies are preferably monoclonal. Monoclonal antibodies may be produced by methods known in the art. These methods include the immunological method described by Kohler and Milstein in Nature 256, 495-497 (1975) and the recombinant DNA method described by Huse et al in Science 246, 1275-1281 (1989).

[0080] Mammals, including humans, suffering from diseases caused by infection with N. meningitidis may be treated by administering antibodies specific to a member of the hemolysin family of toxins. Antibodies raised against a member of the hemolysin family of toxins from any genera of bacteria are suitable, although antibodies raised against a polypeptide comprising an amino acid sequence present in N. meningitidis is preferred.

[0081] For therapeutic purposes, it is necessary for the antigenic polypeptides of the invention to produce neutralizing antibodies. Neutralizing antibodies are antibodies that significantly inhibit the growth of or kill the bacterial cells and/or significantly neutralize the toxin function of the polypeptide in vitro or in vivo. Growth of the bacteria is significantly inhibited or the toxin function of the polypeptide is significantly neutralized in vivo if the inhibition or neutralization is sufficient to prevent or reduce the symptoms of the disease of a mammal infected with the disease.

[0082] Neutralizing antibodies may also be used to produce anti-idiotypic antibodies useful as vaccines for immunizing mammals, including humans, suffering from diseases caused by infection with N. meningitidis. Anti-idiotypic antibodies are prepared in accordance with methods known in the art.

Nucleic Acid Molecules

[0083] The present invention also includes isolated nucleic acid molecules that encode any of the polypeptides of the invention described above. The nucleic acid molecule may be DNA or RNA.

[0084] The utility of the nucleic acid molecule lies in its ability to be used as a probe for detecting N. meningitidis, as explained below, or to produce a polypeptide of the invention, as explained above. The nucleic acid molecule may be prepared by methods known in the art. Suitable methods include isolating the DNA from N. meningitidis or synthesizing the DNA in accordance with known procedures as described above.

Probes

[0085] The present invention further provides a method of detecting the presence of N. meningitidis in a sample. The method involves use of a probe that recognizes a polypeptide that is a member of the hemolysin family of toxins, and, in particular, a member of the hemolysin family of toxins present in N. meningitidis, or a gene encoding such a polypeptide. The probe recognizes N. meningitidis if present in the sample.

[0086] The probe may be an antibody, preferably a monoclonal antibody. The antibodies may be prepared as described above.

[0087] Methods are known for detecting polypeptides with antibodies. For example, a polypeptide may be immobilized on a solid support. Immobilization of the polypeptide may occur through an immobilized first antibody specific for the polypeptide. The immobilized first antibody is incubated with a sample suspected of containing the polypeptide. If present, the polypeptide binds to the first antibody.

[0088] A second antibody, also specific for the polypeptide, binds to the immobilized polypeptide. The second antibody may be labelled by methods known in the art. Non-immobilized materials are washed away, and the presence of immobilized label indicates the presence of the polypeptide. This and other immunoassays are described by David, et al., in U.S. Pat. No. 4,376,110 assigned to Hybritech, Inc., La Jolla, Calif.

[0089] The probe may also be a nucleic acid molecule that recognizes a RNA or DNA molecule that encodes a member of the hemolysin family of toxins present in N. meningitidis. Methods for determining whether a nucleic acid molecule probe recognizes a specific nucleic acid molecule in a sample are known in the art. Generally, a labelled probe that is complementary to a nucleic acid sequence suspected of being in a sample is prepared. The presence of probe hybridized to the target nucleic acid molecule indicates the presence of the nucleic acid molecule. Suitable methods are described by Schneider et al in U.S. Pat. No. 4,882,269, which is assigned to Princeton University, and by Segev in PCT Application WO 90/01069. The Schneider et al patent and the Segev application are both licensed to ImClone Systems Inc., New York City.

[0090] The probes described above are labelled in accordance with methods known in the art. Methods for labelling antibodies have been described, for example, by Hunter and Greenwood in Nature 144, 945 (1962) and by David et al in Biochemistry 13, 1014-1021 (1974). Additional methods for labelling antibodies have been described in U.S. Pat. Nos. 3,940,475 and 3,645,090. Methods for labelling oligonucleotide probes have been described, for example, by Leary et al, Proc. Natl. Acad. Sci. USA (1983) 80:4045; Renz and Kurz, Nucl. Acids Res. (1984) 12:3435; Richardson and Gumport, Nucl. Acids Res. (1983) 11:6167; Smith et al, Nucl. Acids Res. (1985) 13:2399; and Meinkoth and Wahl, Anal. Biochem. (1984) 138:267.

[0091] The label may be radioactive. Some examples of useful radioactive labels include ³²P, ¹²⁵I, ¹³¹I, and ³H. Use of radioactive labels have been described in U.K. 2,034,323, U.S. Pat. No. 4,358,535, and U.S. Pat. No. 4,302,204.

[0092] Some examples of non-radioactive labels include enzymes, chromophors, atoms and molecules detectable by electron microscopy, and metal ions detectable by their magnetic properties.

[0093] Some useful enzymatic labels include enzymes that cause a detectable change in a substrate. Some useful enzymes and their substrates include, for example, horseradish peroxidase (pyrogallol and o-phenylenediamine), beta-galactosidase (fluorescein-beta-D-galactopyranoside), and alkaline phosphatase (5-bromo-4-chloro-3-indolyl phosphate/nitro blue tetrazolium). The use of enzymatic labels have been described in U.K. 2,019,404, EP 63,879, and by Rotman, Proc. Natl. Acad. Sci., 47, 1981-1991 (1961).

[0094] Useful chromophores include, for example, fluorescent, chemiluminescent, and bioluminescent molecules, as well as dyes. Some specific chromophores useful in the present invention include, for example, fluorescein, rhodamine, Texas red, phycoerythrin, umbelliferone, luminol.

[0095] The labels may be conjugated to the antibody or nucleotide probe by methods that are well known in the art. The labels may be directly attached through a functional group on the probe. The probe either contains or can be caused to contain such a functional group. Some examples of suitable functional groups include, for example, amino, carboxyl, sulfhydryl, maleimide, isocyanate, isothiocyanate.

[0096] The label may also be conjugated to the probe by means of a ligand attached to the probe by a method described above and a receptor for that ligand attached to the label. Any of the known ligand-receptor combinations is suitable. The biotin-avidin combination is preferred.

[0097] The polypeptide of the invention may be used to detect the presence of antibodies specific for N. meningitidis in a sample. The method comprises preparing a polypeptide containing a segment having an amino acid sequence that is substantially homologous to a member of the hemolysin family of toxins. The polypeptide may be prepared as described above. Preferably, the polypeptide comprises a segment having an amino acid sequence that is present in N. meningitidis.

[0098] The sample may, for example, be from a patient suspected of being infected with N. meningitidis. Suitable assays are known in the art, such as the standard ELISA protocol described by R. H. Kenneth, “Enzyme-Linked Antibody Assay with Cells Attached to Polyvinyl Chloride Plates” in Kenneth et al, Monoclonal Antibodies, Plenum Press, N.Y., page 376 (1981).

[0099] Briefly, plates are coated with antigenic polypeptide at a concentration sufficient to bind detectable amounts of the antibody. After incubating the plates with the polypeptide, the plates are blocked with a suitable blocking agent, such as, for example, 10% normal goat serum. The sample, such as patient sera, is added and titered to determine the endpoint. Positive and negative controls are added simultaneously to quantitate the amount of relevant antibody present in the unknown samples. Following incubation, the samples are probed with goat anti-human Ig conjugated to a suitable enzyme. The presence of anti-polypeptide antibodies in the sample is indicated by the presence of the enzyme.

[0100] Antibodies raised against polypeptides of the present invention are capable of recognizing N. meningitidis and distinguishing meningococcal cells from gonococcal cells in a sample. The A4.85 monoclonal antibody, for example, recognizes a polypeptide expressed by iron-stressed meningococcal cells. A4.85 does not, however, recognize any proteins in iron-stressed N. gonorrhoeae.

[0101] The antibodies may be labelled by known methods as described above. Assays for distinguishing iron-stressed meningococcal cells from iron-stressed gonococcal cells follow known formats, such as standard blot and ELISA formats.

EXAMPLES Example 1 Isolation of A4.85 MAb

[0102] Bacterial outer membranes are prepared from iron-stressed cultures of Neisseria meningitidis strain FAM20 as follows. FAM20 is inoculated into chelexed defined medium (CDM, West et al, J. Bacteriology 169, 3414 (1987)). This medium allows growth only until iron stores within the bacteria have been depleted. During this time, a set of proteins that are regulated by the availability of iron become expressed. Bacteria are harvested and outer membranes are prepared as described by Dyer et al in Infection and Immunity 56, 977 (1988).

[0103] Three to five BALB/c female mice are immunized with iron-stressed FAM20 outer membranes by either the intramuscular (im) or intraperitoneal (ip) routes. With the im route, 100 μg of antigen (Ag) is emulsified in complete Freund's adjuvant and injected on two different sites on day zero, followed by booster doses two weeks apart with the Ag now emulsified in incomplete Freund's adjuvant. The ip route involves immunization with 100 μg of Ag on days zero, 7, 14 and 28. Serum antibody levels are checked by either ELISA or Western blotting three days following the final boost to determine serum antibody levels. Mice are given a final boost ip on each of three consecutive days before the fusion. On the day of the fusion, mice are sacrificed by cervical dislocation and the spleens are removed aseptically. Spleen cells are extracted by teasing the cells out of the sac using two bent 19 ga needles. Extracted cells are resuspended to give single cell suspensions.

[0104] Mouse myeloma cells, SP2.0-AG14 (ATCC CRL 1581), that have been grown in Dulbecco's Modified Eagle's Medium/Ham's F-12 (DMEM/F12) supplemented with 15% fetal calf serum (FCS), are used as the fusion partner. Cells are mixed in a 10:1 ratio of spleen:myeloma cells and pelleted together in a 50 ml centrifuge tube. The supernatant is aspirated off leaving a dry pellet to which 1 ml of 50% polyethylene glycol (PEG) (prewarmed to 37° C.) is added. The cells are gently resuspended and allowed to sit at room temperature for 2 minutes, after which 1 ml of DMEM/F12 without added sera is added and the cells gently resuspended. The cells are then further diluted and resuspended with 2, 4, 8 and 16 ml of DMEM/F12 added at two-minute intervals. The cells are then pelleted and the supernatant aspirated. Two ml of DMEM/F12 supplemented with 15% FCS is carefully added to avoid resuspension of the pellet and then incubated for one hour at 37° C.

[0105] At the end of the 1 hour incubation, the suspension is diluted to a final concentration of 1×10⁶ cells/ml. This suspension is then poured into tissue culture flasks and incubated overnight. The next day an equal volume of culture media supplemented with 2×HAT (hypoxanthine, aminopterin, thymidine) components are plated out into 96-well plates with 200 μl/well with 1×10⁵ spleen cells/well. Plated cells are fed every 4-5 days after the fusion by aspiration of half the media from the wells and addition of fresh 1×HAT media. The wells are scored for growth after 10-14 days, and growing wells are tested for presence of secreted antibody by screening the culture supernatants by either an ELISA or Western blotting. Wells that prove positive on assay are expanded for growth into 24-well culture dishes in culture media with HT supplements (no aminopterin) and re-tested. Those proving positive on re-testing are expanded further into larger tissue culture vessels and then cloned twice by limiting dilution.

[0106] A cell line (A4.85) that arose from a single mouse spleen cell was isolated. A4.85 produces a monoclonal antibody (Mab) that reacts with several protein species (70 kilodaltons to several hundred kilodaltons in mass) on a Western blot of FAM20 outer membranes, each of whose synthesis is repressed by the presence of iron in the bacterial growth medium.

Example 2A Isolation of Genomic Clones

[0107] A. Library Construction

[0108] A library of Neisseria meningitidis strain FAM20 chromosomal DNA is constructed in the bacteriophage vector lambda-gt11 as follows. FAM20 chromosomal DNA is isolated by standard methods (Maniatis et al, 1982). The DNA is sheared by sonication to fragment sizes of approximately 300-1000 bp. Synthetic EcoRI linkers are ligated to the ends of these molecules, followed by cleavage with EcoRI restriction endonuclease to generate EcoRI restriction sites at the end of each molecule. The resulting fragments are ligated with EcoRI-cleaved lambda-gt11 DNA (Maniatis et al, Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1982)). The ligated DNA is packaged into lambda phage heads using lambda packaging extracts (Promega Corp., Madison, Wis.), according to manufacturer's instructions.

[0109] B. Library Screening and Isolation of DNA

[0110] The library created above is screened with the A4.85 Mab to detect clones that express the epitope recognized by A4.85. 500,000 recombinant plaques from the lambda-gt11 expression library are screened by the method of Maniatis et al (1982). A pure clone reacting with the A4.85 Mab is isolated by re-plating and screening the reactive plaque twice. The meningococcal insert DNA from the pure lambda clone (lambda 4.85) is amplified by the polymerase chain reaction (PCR) technique using a kit from Perkin-Elmer/Cetus. The PCR-amplified DNA is cloned into the sequencing vector M13 mp19 (Maniatis et al, 1982) and the DNA sequence determined by the dideoxy chain termination method of Sanger et al (Proc. Natl. Acad. Sci. USA 74, 5463-5467 (19877)) using the Sequenase kit (Stratagene, La Jolla, Calif.).

[0111] The cloned meningococcal DNA is labelled with ³²P by the random primed method with a kit from Boehringer-Mannheim (Indianapolis, Ind.) and is used in Southern hybridizations (Maniatis et al, 1982) to identify DNA restriction fragments in the FAM20 chromosome adjacent to the DNA cloned in lambda 4.85. Chromosomal Sau3A I fragments of approximately 560 and 1600 bp hybridize to the cloned meningococcal DNA. FAM20 DNA is cleaved with Sau3A I and fractionated on a preparative agarose gel. Two size fractions are isolated, one of 400-700 bp and one of 1400-1800 bp.

[0112] The 560 bp Sau3A I fragment is cloned by ligating the 400-700 bp fraction of FAM20-Sau3A I fragments with BamHI-cleaved plasmid PBR322 (Maniatis et al, 1982). The desired clones of the 560 bp fragment are identified by hybridization of bacterial colonies containing recombinant plasmids with ³²P-labelled lambda 4.85 insert DNA (Maniatis et al, 1982). Plasmid DNA (pUNCH201) from a pure colony hybridizing with the DNA probe is prepared and its sequence determined using Sequenase as modified for use in double-strand sequencing (Kraft et al, BioTechniques 6, 544 (1988)). Southern hybridization is used to verify that the cloned fragment is representative of the fragment intact in the FAM20 genome.

[0113] To clone the 1600 bp fragment, the ends of the 1400-1800 bp fraction of FAM20-Sau3A I fragments are made blunt by reaction with Klenow enzyme and DNA nucleotides. Synthetic EcoRI linkers are added to these molecules, followed by ligation with EcoRI-cleaved, alkaline-phosphatase-treated lambda ZAP DNA (Stratagene, LaJolla, Calif.) in accordance with technical information supplied with the lambda ZAP kit. Ligated DNA is packaged into lambda heads using Packagene lambda packaging extracts (Promega). The library of 1400-1800 bp FAM20-Sau3A I fragments is screened with a ³²P-labelled oligonucleotide (SAT1), which is synthesized to correspond to DNA sequences at one end of the lambda 4.85 insert (5′ GCCATTGCCACTGTAGATA 3′). A lambda ZAP plaque hybridizing with the SAT1 oligonucleotide is purified as above. The interior portion of this lambda ZAP clone (lambda ZAP202) is “excised” by the addition of helper bacteriophage. The excision results in a multicopy plasmid (pUNCH202) containing the cloned meningococcal insert. Southern hybridization is used to verify that the cloned fragment is representative of the fragment intact in the FAM20 genome. The sequence of the cloned DNA fragment is determined by double-strand sequencing as described above.

[0114] To obtain the entire DNA sequence of the gene for an antigenic iron repressible protein (frpA) from N. meningitidis related to the hemolysin family of toxins, two additional clones, pUNCH206 and pUNCH210, are isolated. These clones contain fragments flanking pUNCH201 and represent the entirety of the frpA gene.

[0115] To isolate pUNCH206, a 2.7 kilobase (kb) EcoRI to HincII fragment overlapping pUNCH201 is cloned as follows. FAM20 chromosomal DNA is digested to completion with HincII. EcoRI linkers are ligated to the ends of these fragments, which are then ligated to EcoRI-digested lambda ZAP. The desired clone is identified by hybridization with ³²P-labelled pUNCH201 insert. The interior portion of this clone is “excised” by the addition of helper bacteriophage, and is designated pUNCH206. The pUNCH206 insert contains the 3′ end of the frpA gene.

[0116] To obtain pUNCH210, a 4.3 kb SpeI to ClaI fragment overlapping the pUNCH206 insert is cloned as follows. FAM20 DNA is digested with SpeI and NheI, the fragments are separated by pulsed-field gel electrophoresis using a CHEF apparatus and are transferred to a BA-S85 membrane. (Schleicher & Schuell, Keene, N.H.).

[0117] The fragment of interest is identified by hybridization. This fragment is electrophoresed from the gel onto DE81 DEAE-cellulose paper and purified. This DNA is digested with ClaI and the ends made blunt by treatment with Klenow enzyme and DNA nucleotides. This is ligated with lambda ZAP which had been digested with EcoRI, then treated with Klenow fragment. The desired clone is identified by hybridization with ³²P-labelled pUNCH210 insert. The interior portion of this clone is “excised” by the addition of helper bacteriophage, and is designated pUNCH210. The pUNCH210 insert contains the 5′ end of the frpA gene.

[0118] The adjoined sequence of pUNCH210 and pUNCH206 reveals the presence of an open reading frame that contains the entirety of the cloned DNA. The DNA sequence is included in FIG. 1. See Seq. ID No. 1. The amino acid sequence predicted by the sequence contains 1115 amino acids. The putative amino acid sequence is shown as FIG. 2. See Seq. ID No. 2.

[0119] As determined by FASTA sequence comparison searches (see above), both the DNA and the deduced polypeptide sequence from this region have a high degree of similarity with a family of hemolysin bacterial toxins. For example, the DNA sequence shown in FIG. 1 (Seq. ID No. 1.) exhibits 54% identity with the cya gene (adenylate cyclase) from B. pertussis; 60% identity with the hlyA, hlyB, hlyC and hlyD gene from E. coli (hemolysin); 65% identity with hlyA, hlyB and hlyC gene (hemolysin) from E. coli; 56% identity with the leukotoxin gene from A. actinomycetemcomitans; 56% identity with the hemolysin gene from A. pleuropneumoniae; 60% identity with the leukotoxin gene from P. haemolytica; 62% identity with the Al leukotoxin gene from P. haemolytica; and 57% identity with protease B gene of E. chrysanthemi.

[0120] The amino acid sequence predicted from the DNA sequence exhibited 25%-28% identity with leukotoxin, 22%-28% identity with hemolysin; and 30% identity with adenylate cyclase.

[0121] Meningococcal strain FAM20 contains at least two copies of DNA that encode the polypeptides of the invention. This can be demonstrated by digesting genomic DNA with the infrequent cutters BglII, SpeI, NheI, and combinations of NheI and SpeI. Southern blots of the digested DNA separated by pulse field gradient electrophoresis reveal two major bands that hybridize under stringent conditions to gene probes containing fragments of the sequence of the gene that encodes the polypeptide of the invention.

[0122] The remainder of the gene encoding the iron-regulated polypeptide of the invention is isolated in a manner similar to that described above for isolating pUNCH201 and pUNCH202. DNA restriction fragments either flanking the ends of the region already cloned or containing the entire region are identified by Southern hybridization using oligonucleotide probes derived from previously determined DNA sequence. These fragments are cloned into either plasmid or bacteriophage vectors as described above for pUNCH201 and pUNCH202. The DNA sequence of newly cloned fragments is determined as above, and reveals when either end of the gene is reached. If the gene is isolated on a single DNA fragment, it is expressed in an in vitro assay to verify that the protein that is encoded by this gene reacts with the A4.85 Mab. If the gene is not cloned intact on a single DNA fragment, it is reconstructed through standard molecular biology techniques to yield the intact gene (Carbonetti, Proc. Natl. Acad. Sci. USA 84, 9084 (1987)).

[0123] For example, DNA fragments from one of the two copies of the structural genes coding for the polypeptide of the invention were purified from agarose gels, cloned and sequenced. FIG. 1 includes the DNA sequence. See Seq. ID No. 1.

Example 2B Western Blot and Molecular Weight

[0124] The full length polypeptide obtained from meningococcal strain FAM20 exhibits a molecular weight of 230-250 kD when subjected to Western blot analysis. Western blots may be carried out as follows:

[0125] Iron-starved whole cells of FAM20 are prepared in accordance with the method of West and Sparling, J. Bacteriol. 169, 3414-3421 (1987). The cells are washed in ice-cold Davis Minimal Medium A (Lederberg, Methods in Med. Res., 3:5 (1950)), immediately cooled on ice, and ruptured in a French pressure cell at 0° C. and 20,000 psi. The resulting mixture is centrifuged for 10 minutes at 20,000G, and the pellet solubilized in boiling SDS. The solubilized membrane proteins are separated by standard 7.5% SDS-PAGE in Laemli buffer, which was described by Laemli in Nature 227, 680-685 (1970). The proteins are transferred (16 hours, 80 μA) onto Optibind nitrocellulose membranes (available from Schleicher & Schuell). The membranes are blocked for 1 hour in 5% BSA in TBS (20 mM Tris, 500 Mm NaCl, pH 7.5); rinsed for 5 minutes in TBS; incubated for 1 hour with 1:2 dilution of monoclonal antibody A4.85 (see above) in 5% BSA; washed twice for 5 minutes in TBS and 0.05% Tween 20; incubated for 1 hour in a secondary antibody (goat anti-mouse lgG alkaline phosphatase conjugate) diluted in 5% BSA, available from BioRad (dilution=1:3000) or Sigma (dilution=1:1000); washed twice for 5 minutes in TBS/Tween; washed again for 5 minutes in TBS; and developed with an alkaline phosphatase substrate comprising 45 μl Nitro Blue Tetrazolin, available from Sigma (75 mg/ml); 35 μl 5-bromo-4-chloro-3-indolylphosphate, p-tolnidine salt (50 mg/ml) in 10 ml of carbonate buffer, pH 9.8 (0.1 M NaHCO₃; 1 mM MgCl₂)

Example 3 Assay for Antibody in Sample

[0126] A standard ELISA protocol is used to screen for the presence of antibodies against the polypeptide in proteins. Briefly, 96 well microtiter plates are coated with the antigen at concentrations varying from 50-1000 ng per well in a high pH (9.6) carbonate buffer. The plates are incubated overnight at 9° C. and blocked with 10% normal goat serum for one hour at 37° C. Patient sera is added and titered to determine the endpoint. Control positive and negative sera is added at the same time to quantitate the amount of relevant antibody present in the unknown samples. After a 2-3 hour incubation at 37° C., samples are probed with goat anti-human Ig conjugated to horseradish peroxidase. Positive samples are determined by using TMB.

[0127] The invention as claimed is enabled in accordance with the specification and readily available references and starting materials. Nevertheless, the following cell lines have been deposited in the American Type Culture Collection, Bethesda, Md. on Jul. 12, 1990 in order to facilitate the making and using of the invention:

[0128] Meningococcal cell line FAM18 (Accession Number 55071)

[0129] Meningococcal cell line FAM20 (Accession Number 55072)

[0130] Hybridoma cell line A4.85 (Accession Number HB 10504)

[0131] In addition, the following brochures containing useful protocols and information are available in the file history of this specification.

[0132] “Predigested Lambda Zap/Eco RI Cloning Kit Instruction Manual,” Stratagene, La Jolla, Calif. (Nov. 20, 1987);

[0133] “Gigapack Plus” (for packaging recombinant lambda phage), Stratagene, La Jolla, Calif. (Apr. 25, 1988); and

[0134] “picoBlue Immunoscreening Kit” Instruction Manual,” Stratagene, La Jolla, Calif. (May 19, 1989).

1 4 1 3758 DNA Neisseria Meningitidis misc_feature (298)..(3642) mat-peptide 1 tatatgtctt tatttgaata tatcttacga tggggaaata tttatatatt ttataataaa 60 ttttactcat ttgctaatat gtcatggaat attacttgta ttttgtagaa tttttccata 120 tgaaaatatt ccatttacta tttttctgaa ctttattagt ttatttttaa tatttttacc 180 tcttatattt accataagag agctaattga ttcatattat attgagtcga taattaattt 240 attcttaatt ttaattcctc acgttatttt tttaatttac ttgaaaggaa agcagat 297 atg aca tct gca aat ttt aat att aac ggt ttt gga gat gtg aaa tta 345 Met Thr Ser Ala Asn Phe Asn Ile Asn Gly Phe Gly Asp Val Lys Leu 1 5 10 15 aca ccc tat tca cca ctc ttg gga tat aaa gct tgg gat tca ttt att 393 Thr Pro Tyr Ser Pro Leu Leu Gly Tyr Lys Ala Trp Asp Ser Phe Ile 20 25 30 ggt tct att caa tcc tta tct gat tta atc tat aat gtg gat aac aat 441 Gly Ser Ile Gln Ser Leu Ser Asp Leu Ile Tyr Asn Val Asp Asn Asn 35 40 45 aga aat aaa atg gaa att act gtt aat aat gct atc caa gct gca gat 489 Arg Asn Lys Met Glu Ile Thr Val Asn Asn Ala Ile Gln Ala Ala Asp 50 55 60 agc ttt tta agc agt att gga aga gat aac aaa ata aca aat act gct 537 Ser Phe Leu Ser Ser Ile Gly Arg Asp Asn Lys Ile Thr Asn Thr Ala 65 70 75 80 tct tta ctt gca tcc ctc gat aac att ttt tta aat tta aga aat gta 585 Ser Leu Leu Ala Ser Leu Asp Asn Ile Phe Leu Asn Leu Arg Asn Val 85 90 95 tct cga gat ata cga gaa aca gga aaa ttt aaa cct aat gat att caa 633 Ser Arg Asp Ile Arg Glu Thr Gly Lys Phe Lys Pro Asn Asp Ile Gln 100 105 110 caa gca att ggt gat ata ttc att gct gct ggt gat gga tta caa tat 681 Gln Ala Ile Gly Asp Ile Phe Ile Ala Ala Gly Asp Gly Leu Gln Tyr 115 120 125 ata aaa caa caa aca gag gcg atg gct caa agc aaa ttc tta cca act 729 Ile Lys Gln Gln Thr Glu Ala Met Ala Gln Ser Lys Phe Leu Pro Thr 130 135 140 aaa tta aaa act ggt tta aat gat gtc ctt aat tct aga atg cta aaa 777 Lys Leu Lys Thr Gly Leu Asn Asp Val Leu Asn Ser Arg Met Leu Lys 145 150 155 160 tcc tct act gtt tta cag cat gaa ttg aat tat ttg gga ttt aaa ata 825 Ser Ser Thr Val Leu Gln His Glu Leu Asn Tyr Leu Gly Phe Lys Ile 165 170 175 aag gat tat gga aac gag agg ctt ggc gaa tct ata atg aat ata gat 873 Lys Asp Tyr Gly Asn Glu Arg Leu Gly Glu Ser Ile Met Asn Ile Asp 180 185 190 gat ttt aca cca agt aag ata gca aac ttt ttt gcg gat cct gat aca 921 Asp Phe Thr Pro Ser Lys Ile Ala Asn Phe Phe Ala Asp Pro Asp Thr 195 200 205 tac agc aat gta tta gaa gaa gta tct agg ttt ata tat tcc tta gtt 969 Tyr Ser Asn Val Leu Glu Glu Val Ser Arg Phe Ile Tyr Ser Leu Val 210 215 220 cct gat gat gca aac cct tgg aaa ggg ggc gaa gat tat att gga cga 1017 Pro Asp Asp Ala Asn Pro Trp Lys Gly Gly Glu Asp Tyr Ile Gly Arg 225 230 235 240 ggg ata agt gaa tgg gga gag tta ctg gaa aaa tgg tat aaa caa gat 1065 Gly Ile Ser Glu Trp Gly Glu Leu Leu Glu Lys Trp Tyr Lys Gln Asp 245 250 255 ttt ctc cct tat ctt gaa aaa gaa tgg gac caa ttt ccg aaa ttt gaa 1113 Phe Leu Pro Tyr Leu Glu Lys Glu Trp Asp Gln Phe Pro Lys Phe Glu 260 265 270 gat tgg ctg cct gaa ttc cct gaa tgg gca aga gag tgg ttg aaa tta 1161 Asp Trp Leu Pro Glu Phe Pro Glu Trp Ala Arg Glu Trp Leu Lys Leu 275 280 285 gat ccc aaa cgt tca ggc aaa tat cat gtc tac gac ccc ctc gcc cta 1209 Asp Pro Lys Arg Ser Gly Lys Tyr His Val Tyr Asp Pro Leu Ala Leu 290 295 300 gat cta gac ggc gac ggt ata gaa acc gtt gct gcc aaa ggc ttt gca 1257 Asp Leu Asp Gly Asp Gly Ile Glu Thr Val Ala Ala Lys Gly Phe Ala 305 310 315 320 ggt gca ttg ttc gac cac cgc aat caa ggc atc cgc acc gcc acc ggt 1305 Gly Ala Leu Phe Asp His Arg Asn Gln Gly Ile Arg Thr Ala Thr Gly 325 330 335 tgg gtt tct gcc gat gac ggt tta ctc gtc cgc gat ttg aac ggc aac 1353 Trp Val Ser Ala Asp Asp Gly Leu Leu Val Arg Asp Leu Asn Gly Asn 340 345 350 ggc atc atc gac aac ggc gcg gaa ctc ttc ggc gac aac acc aaa ctg 1401 Gly Ile Ile Asp Asn Gly Ala Glu Leu Phe Gly Asp Asn Thr Lys Leu 355 360 365 gca gac ggt tct ttt gcc aaa cac ggc tat gca gct ttg gcc gaa ttg 1449 Ala Asp Gly Ser Phe Ala Lys His Gly Tyr Ala Ala Leu Ala Glu Leu 370 375 380 gat tca aac ggc gac aac atc atc aac gcg gca gac gcc gca ttc caa 1497 Asp Ser Asn Gly Asp Asn Ile Ile Asn Ala Ala Asp Ala Ala Phe Gln 385 390 395 400 acc ctg cgt gta tgg cag gat ctc aac cag gac ggc att tcc caa gct 1545 Thr Leu Arg Val Trp Gln Asp Leu Asn Gln Asp Gly Ile Ser Gln Ala 405 410 415 aat gaa ttg cgt acc ctt gaa gaa ttg ggt atc caa tct ttg gat ctc 1593 Asn Glu Leu Arg Thr Leu Glu Glu Leu Gly Ile Gln Ser Leu Asp Leu 420 425 430 gcc tat aaa gat gta aat aaa aat ctc ggt aac ggt aac act ttg gct 1641 Ala Tyr Lys Asp Val Asn Lys Asn Leu Gly Asn Gly Asn Thr Leu Ala 435 440 445 cag caa ggc agc tat acc aaa aca gac ggt aca acc gca aaa atg ggg 1689 Gln Gln Gly Ser Tyr Thr Lys Thr Asp Gly Thr Thr Ala Lys Met Gly 450 455 460 gat tta ctt tta gca gcc gac aat ctg cac agc cgc ttc aaa gac aaa 1737 Asp Leu Leu Leu Ala Ala Asp Asn Leu His Ser Arg Phe Lys Asp Lys 465 470 475 480 gtg gaa ctc act gcc gaa cag gca aaa gcc gcc aat ctt gcg ggc atc 1785 Val Glu Leu Thr Ala Glu Gln Ala Lys Ala Ala Asn Leu Ala Gly Ile 485 490 495 ggc cgt ctg cgc gat ttg cgc gaa gct gcc gca ttg tcc ggc gat ttg 1833 Gly Arg Leu Arg Asp Leu Arg Glu Ala Ala Ala Leu Ser Gly Asp Leu 500 505 510 gcc aat atg ctg aaa gct tat tct gcc gcc gaa act aaa gaa gca cag 1881 Ala Asn Met Leu Lys Ala Tyr Ser Ala Ala Glu Thr Lys Glu Ala Gln 515 520 525 ttg gca ttg tta gat aat ttg att cac aaa tgg gcg gaa acc gat tcg 1929 Leu Ala Leu Leu Asp Asn Leu Ile His Lys Trp Ala Glu Thr Asp Ser 530 535 540 aac tgg ggc aaa aaa tcg cca atg cga ctt tca acc gat tgg acg caa 1977 Asn Trp Gly Lys Lys Ser Pro Met Arg Leu Ser Thr Asp Trp Thr Gln 545 550 555 560 acg gct aat gaa ggt att gca ctg aca cca tcc caa gta gca caa cta 2025 Thr Ala Asn Glu Gly Ile Ala Leu Thr Pro Ser Gln Val Ala Gln Leu 565 570 575 aaa aag aac gct tta gtt tcc ctt tct gat aaa gct aaa gca gct att 2073 Lys Lys Asn Ala Leu Val Ser Leu Ser Asp Lys Ala Lys Ala Ala Ile 580 585 590 gac gcc gcc cgc gac cgc att gcc gtg ctt gat gcc tac acg ggg cag 2121 Asp Ala Ala Arg Asp Arg Ile Ala Val Leu Asp Ala Tyr Thr Gly Gln 595 600 605 gat tcc agc aca ctc tat tac atg agc gaa gaa gac gcg ctt aat atc 2169 Asp Ser Ser Thr Leu Tyr Tyr Met Ser Glu Glu Asp Ala Leu Asn Ile 610 615 620 gtc aaa gta acc aac gat aca tac gac cat ctc gcc aaa aac atc tac 2217 Val Lys Val Thr Asn Asp Thr Tyr Asp His Leu Ala Lys Asn Ile Tyr 625 630 635 640 caa aac ctg ttg ttc caa acc cgt ttg cag cca tat ttg aat caa atc 2265 Gln Asn Leu Leu Phe Gln Thr Arg Leu Gln Pro Tyr Leu Asn Gln Ile 645 650 655 agt ttc aaa atg gaa aat gat acg ttc act ttg gat ttt agt ggt ctt 2313 Ser Phe Lys Met Glu Asn Asp Thr Phe Thr Leu Asp Phe Ser Gly Leu 660 665 670 gtt caa gca ttt aac cat gtc aaa gaa act aat ccg caa aaa gct ttt 2361 Val Gln Ala Phe Asn His Val Lys Glu Thr Asn Pro Gln Lys Ala Phe 675 680 685 gtg gat ttg gcc gag atg ctt gca tat ggc gaa ctt cgt tct tgg tat 2409 Val Asp Leu Ala Glu Met Leu Ala Tyr Gly Glu Leu Arg Ser Trp Tyr 690 695 700 gaa ggc cga aga cta atg gcc gat tat gtg gag gag gca aaa aaa gca 2457 Glu Gly Arg Arg Leu Met Ala Asp Tyr Val Glu Glu Ala Lys Lys Ala 705 710 715 720 ggt aaa ttt gaa gat tac cag aaa gtg ttg ggt cag gag acc gtt gca 2505 Gly Lys Phe Glu Asp Tyr Gln Lys Val Leu Gly Gln Glu Thr Val Ala 725 730 735 tta tta gct aaa aca tcg ggt acg caa gca gat gat atc ctg caa aat 2553 Leu Leu Ala Lys Thr Ser Gly Thr Gln Ala Asp Asp Ile Leu Gln Asn 740 745 750 gta ggc ttt ggt cat aat aaa aat gtt tct tta tat ggt aat gac ggc 2601 Val Gly Phe Gly His Asn Lys Asn Val Ser Leu Tyr Gly Asn Asp Gly 755 760 765 aac gac act cta atc ggc ggt gca ggc aat gat tac ttg gag ggc ggc 2649 Asn Asp Thr Leu Ile Gly Gly Ala Gly Asn Asp Tyr Leu Glu Gly Gly 770 775 780 agc ggt tcg gat act tat gtc ttc ggc aaa ggc ttc ggt cag gat acg 2697 Ser Gly Ser Asp Thr Tyr Val Phe Gly Lys Gly Phe Gly Gln Asp Thr 785 790 795 800 gtc tat aat tac gac tac gct acc gga cgc aaa gac atc atc cgc ttt 2745 Val Tyr Asn Tyr Asp Tyr Ala Thr Gly Arg Lys Asp Ile Ile Arg Phe 805 810 815 acc gac ggt att aca gcc gat atg ctg act ttt acc cga gag ggc aac 2793 Thr Asp Gly Ile Thr Ala Asp Met Leu Thr Phe Thr Arg Glu Gly Asn 820 825 830 cat ctt ctt atc aag gca aaa gac gac agt gga caa gtg act gtt cag 2841 His Leu Leu Ile Lys Ala Lys Asp Asp Ser Gly Gln Val Thr Val Gln 835 840 845 tcc tat ttc cag aac gat ggc tca ggt gct tac cgt atc gat gag att 2889 Ser Tyr Phe Gln Asn Asp Gly Ser Gly Ala Tyr Arg Ile Asp Glu Ile 850 855 860 cat ttc gat aac ggc aaa gta ctg gat gtt gcc act gtc aaa gaa ctg 2937 His Phe Asp Asn Gly Lys Val Leu Asp Val Ala Thr Val Lys Glu Leu 865 870 875 880 gta cag caa tcc acc gac ggt tcg gac aga ttg tat gcc tac caa tcc 2985 Val Gln Gln Ser Thr Asp Gly Ser Asp Arg Leu Tyr Ala Tyr Gln Ser 885 890 895 gga agt acc tta aat ggc gga ttg ggc gat gac tat ctg tac ggt gcc 3033 Gly Ser Thr Leu Asn Gly Gly Leu Gly Asp Asp Tyr Leu Tyr Gly Ala 900 905 910 gac ggg aat gac ctg ctg aat ggt gat gca ggc aac gac agt atc tac 3081 Asp Gly Asn Asp Leu Leu Asn Gly Asp Ala Gly Asn Asp Ser Ile Tyr 915 920 925 agt ggc aat ggc aat gat acg ctc gat gga gga gaa ggc aac gac gcc 3129 Ser Gly Asn Gly Asn Asp Thr Leu Asp Gly Gly Glu Gly Asn Asp Ala 930 935 940 ctg tac ggc tat aat ggt aac gat gca ctg aat ggt ggc gaa ggc aat 3177 Leu Tyr Gly Tyr Asn Gly Asn Asp Ala Leu Asn Gly Gly Glu Gly Asn 945 950 955 960 gat cat ttg aac ggc gaa gac ggt aac gac act cta atc ggc ggt gca 3225 Asp His Leu Asn Gly Glu Asp Gly Asn Asp Thr Leu Ile Gly Gly Ala 965 970 975 ggc aat gat tac ttg gag ggc ggc agc ggt tcg gat act tat gtc ttc 3273 Gly Asn Asp Tyr Leu Glu Gly Gly Ser Gly Ser Asp Thr Tyr Val Phe 980 985 990 ggc gaa ggc ttc ggt cag gat acg gtc tat aat tac cat gtg gat aaa 3321 Gly Glu Gly Phe Gly Gln Asp Thr Val Tyr Asn Tyr His Val Asp Lys 995 1000 1005 aac tct gac act atg cac ttt aaa gga ttt aaa gca gca gat gtt 3366 Asn Ser Asp Thr Met His Phe Lys Gly Phe Lys Ala Ala Asp Val 1010 1015 1020 cat ttt atc cgt tcc gga agt gat ttg gtg ctt agc gct tct gaa 3411 His Phe Ile Arg Ser Gly Ser Asp Leu Val Leu Ser Ala Ser Glu 1025 1030 1035 caa gac aac gta cgt att tcc gga ttc ttc tat ggt gaa aac cat 3456 Gln Asp Asn Val Arg Ile Ser Gly Phe Phe Tyr Gly Glu Asn His 1040 1045 1050 cgt gta gat aca ttt gtc ttt gat gat gca gct atc agt aat cca 3501 Arg Val Asp Thr Phe Val Phe Asp Asp Ala Ala Ile Ser Asn Pro 1055 1060 1065 gat ttt gcc aag tat att aat gct ggc aat aat ttg gta cag tct 3546 Asp Phe Ala Lys Tyr Ile Asn Ala Gly Asn Asn Leu Val Gln Ser 1070 1075 1080 atg tct gtg ttc ggt tct aat act gct gcg aca gga gga aat gtg 3591 Met Ser Val Phe Gly Ser Asn Thr Ala Ala Thr Gly Gly Asn Val 1085 1090 1095 gat gcc aat ata caa tcc gta cag cag ccg tta ttg gta acg cca 3636 Asp Ala Asn Ile Gln Ser Val Gln Gln Pro Leu Leu Val Thr Pro 1100 1105 1110 tct gca taaggagcct aatcacattc atggcttaaa ctgaaaaaca gcaatcaagt 3692 Ser Ala 1115 ttattttgat tgctgttttt cttaatattg ggataagggt cgagaccttt gcaaaaatag 3752 tctgtt 3758 2 1115 PRT Neisseria Meningitidis 2 Met Thr Ser Ala Asn Phe Asn Ile Asn Gly Phe Gly Asp Val Lys Leu 1 5 10 15 Thr Pro Tyr Ser Pro Leu Leu Gly Tyr Lys Ala Trp Asp Ser Phe Ile 20 25 30 Gly Ser Ile Gln Ser Leu Ser Asp Leu Ile Tyr Asn Val Asp Asn Asn 35 40 45 Arg Asn Lys Met Glu Ile Thr Val Asn Asn Ala Ile Gln Ala Ala Asp 50 55 60 Ser Phe Leu Ser Ser Ile Gly Arg Asp Asn Lys Ile Thr Asn Thr Ala 65 70 75 80 Ser Leu Leu Ala Ser Leu Asp Asn Ile Phe Leu Asn Leu Arg Asn Val 85 90 95 Ser Arg Asp Ile Arg Glu Thr Gly Lys Phe Lys Pro Asn Asp Ile Gln 100 105 110 Gln Ala Ile Gly Asp Ile Phe Ile Ala Ala Gly Asp Gly Leu Gln Tyr 115 120 125 Ile Lys Gln Gln Thr Glu Ala Met Ala Gln Ser Lys Phe Leu Pro Thr 130 135 140 Lys Leu Lys Thr Gly Leu Asn Asp Val Leu Asn Ser Arg Met Leu Lys 145 150 155 160 Ser Ser Thr Val Leu Gln His Glu Leu Asn Tyr Leu Gly Phe Lys Ile 165 170 175 Lys Asp Tyr Gly Asn Glu Arg Leu Gly Glu Ser Ile Met Asn Ile Asp 180 185 190 Asp Phe Thr Pro Ser Lys Ile Ala Asn Phe Phe Ala Asp Pro Asp Thr 195 200 205 Tyr Ser Asn Val Leu Glu Glu Val Ser Arg Phe Ile Tyr Ser Leu Val 210 215 220 Pro Asp Asp Ala Asn Pro Trp Lys Gly Gly Glu Asp Tyr Ile Gly Arg 225 230 235 240 Gly Ile Ser Glu Trp Gly Glu Leu Leu Glu Lys Trp Tyr Lys Gln Asp 245 250 255 Phe Leu Pro Tyr Leu Glu Lys Glu Trp Asp Gln Phe Pro Lys Phe Glu 260 265 270 Asp Trp Leu Pro Glu Phe Pro Glu Trp Ala Arg Glu Trp Leu Lys Leu 275 280 285 Asp Pro Lys Arg Ser Gly Lys Tyr His Val Tyr Asp Pro Leu Ala Leu 290 295 300 Asp Leu Asp Gly Asp Gly Ile Glu Thr Val Ala Ala Lys Gly Phe Ala 305 310 315 320 Gly Ala Leu Phe Asp His Arg Asn Gln Gly Ile Arg Thr Ala Thr Gly 325 330 335 Trp Val Ser Ala Asp Asp Gly Leu Leu Val Arg Asp Leu Asn Gly Asn 340 345 350 Gly Ile Ile Asp Asn Gly Ala Glu Leu Phe Gly Asp Asn Thr Lys Leu 355 360 365 Ala Asp Gly Ser Phe Ala Lys His Gly Tyr Ala Ala Leu Ala Glu Leu 370 375 380 Asp Ser Asn Gly Asp Asn Ile Ile Asn Ala Ala Asp Ala Ala Phe Gln 385 390 395 400 Thr Leu Arg Val Trp Gln Asp Leu Asn Gln Asp Gly Ile Ser Gln Ala 405 410 415 Asn Glu Leu Arg Thr Leu Glu Glu Leu Gly Ile Gln Ser Leu Asp Leu 420 425 430 Ala Tyr Lys Asp Val Asn Lys Asn Leu Gly Asn Gly Asn Thr Leu Ala 435 440 445 Gln Gln Gly Ser Tyr Thr Lys Thr Asp Gly Thr Thr Ala Lys Met Gly 450 455 460 Asp Leu Leu Leu Ala Ala Asp Asn Leu His Ser Arg Phe Lys Asp Lys 465 470 475 480 Val Glu Leu Thr Ala Glu Gln Ala Lys Ala Ala Asn Leu Ala Gly Ile 485 490 495 Gly Arg Leu Arg Asp Leu Arg Glu Ala Ala Ala Leu Ser Gly Asp Leu 500 505 510 Ala Asn Met Leu Lys Ala Tyr Ser Ala Ala Glu Thr Lys Glu Ala Gln 515 520 525 Leu Ala Leu Leu Asp Asn Leu Ile His Lys Trp Ala Glu Thr Asp Ser 530 535 540 Asn Trp Gly Lys Lys Ser Pro Met Arg Leu Ser Thr Asp Trp Thr Gln 545 550 555 560 Thr Ala Asn Glu Gly Ile Ala Leu Thr Pro Ser Gln Val Ala Gln Leu 565 570 575 Lys Lys Asn Ala Leu Val Ser Leu Ser Asp Lys Ala Lys Ala Ala Ile 580 585 590 Asp Ala Ala Arg Asp Arg Ile Ala Val Leu Asp Ala Tyr Thr Gly Gln 595 600 605 Asp Ser Ser Thr Leu Tyr Tyr Met Ser Glu Glu Asp Ala Leu Asn Ile 610 615 620 Val Lys Val Thr Asn Asp Thr Tyr Asp His Leu Ala Lys Asn Ile Tyr 625 630 635 640 Gln Asn Leu Leu Phe Gln Thr Arg Leu Gln Pro Tyr Leu Asn Gln Ile 645 650 655 Ser Phe Lys Met Glu Asn Asp Thr Phe Thr Leu Asp Phe Ser Gly Leu 660 665 670 Val Gln Ala Phe Asn His Val Lys Glu Thr Asn Pro Gln Lys Ala Phe 675 680 685 Val Asp Leu Ala Glu Met Leu Ala Tyr Gly Glu Leu Arg Ser Trp Tyr 690 695 700 Glu Gly Arg Arg Leu Met Ala Asp Tyr Val Glu Glu Ala Lys Lys Ala 705 710 715 720 Gly Lys Phe Glu Asp Tyr Gln Lys Val Leu Gly Gln Glu Thr Val Ala 725 730 735 Leu Leu Ala Lys Thr Ser Gly Thr Gln Ala Asp Asp Ile Leu Gln Asn 740 745 750 Val Gly Phe Gly His Asn Lys Asn Val Ser Leu Tyr Gly Asn Asp Gly 755 760 765 Asn Asp Thr Leu Ile Gly Gly Ala Gly Asn Asp Tyr Leu Glu Gly Gly 770 775 780 Ser Gly Ser Asp Thr Tyr Val Phe Gly Lys Gly Phe Gly Gln Asp Thr 785 790 795 800 Val Tyr Asn Tyr Asp Tyr Ala Thr Gly Arg Lys Asp Ile Ile Arg Phe 805 810 815 Thr Asp Gly Ile Thr Ala Asp Met Leu Thr Phe Thr Arg Glu Gly Asn 820 825 830 His Leu Leu Ile Lys Ala Lys Asp Asp Ser Gly Gln Val Thr Val Gln 835 840 845 Ser Tyr Phe Gln Asn Asp Gly Ser Gly Ala Tyr Arg Ile Asp Glu Ile 850 855 860 His Phe Asp Asn Gly Lys Val Leu Asp Val Ala Thr Val Lys Glu Leu 865 870 875 880 Val Gln Gln Ser Thr Asp Gly Ser Asp Arg Leu Tyr Ala Tyr Gln Ser 885 890 895 Gly Ser Thr Leu Asn Gly Gly Leu Gly Asp Asp Tyr Leu Tyr Gly Ala 900 905 910 Asp Gly Asn Asp Leu Leu Asn Gly Asp Ala Gly Asn Asp Ser Ile Tyr 915 920 925 Ser Gly Asn Gly Asn Asp Thr Leu Asp Gly Gly Glu Gly Asn Asp Ala 930 935 940 Leu Tyr Gly Tyr Asn Gly Asn Asp Ala Leu Asn Gly Gly Glu Gly Asn 945 950 955 960 Asp His Leu Asn Gly Glu Asp Gly Asn Asp Thr Leu Ile Gly Gly Ala 965 970 975 Gly Asn Asp Tyr Leu Glu Gly Gly Ser Gly Ser Asp Thr Tyr Val Phe 980 985 990 Gly Glu Gly Phe Gly Gln Asp Thr Val Tyr Asn Tyr His Val Asp Lys 995 1000 1005 Asn Ser Asp Thr Met His Phe Lys Gly Phe Lys Ala Ala Asp Val 1010 1015 1020 His Phe Ile Arg Ser Gly Ser Asp Leu Val Leu Ser Ala Ser Glu 1025 1030 1035 Gln Asp Asn Val Arg Ile Ser Gly Phe Phe Tyr Gly Glu Asn His 1040 1045 1050 Arg Val Asp Thr Phe Val Phe Asp Asp Ala Ala Ile Ser Asn Pro 1055 1060 1065 Asp Phe Ala Lys Tyr Ile Asn Ala Gly Asn Asn Leu Val Gln Ser 1070 1075 1080 Met Ser Val Phe Gly Ser Asn Thr Ala Ala Thr Gly Gly Asn Val 1085 1090 1095 Asp Ala Asn Ile Gln Ser Val Gln Gln Pro Leu Leu Val Thr Pro 1100 1105 1110 Ser Ala 1115 3 9 PRT ArtificialSequence MISC_FEATURE (1)..(9) hemolysin consensus sequence 3 Leu Xaa Gly Gly Xaa Gly Asn Asp Xaa 1 5 4 19 DNA Artificial Sequence primer 4 gccattgcca ctgtagata 19 

What is claimed is:
 1. An isolated, antigenic polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is present in N. meningitidis, and wherein the amino acid sequence is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, and antigenic fragments of such polypeptides.
 2. The polypeptide of claim 1 wherein the segment has at least 100 amino acid residues.
 3. The polypeptide of claim 1 wherein the segment has at least 200 amino acid residues.
 4. The polypeptide of claim 1 in essentially pure form.
 5. The polypeptide of claim 1 wherein the antigenic amino acid sequence is immunogenic.
 6. The polypeptide of claim 1 wherein the amino acid sequence of the polypeptide comprises the sequence shown in FIG.
 2. 7. The polypeptide of claim 1 wherein antibodies against the polypeptide cross-react with at least one other member of the hemolysin family of toxins from other genera of bacteria.
 8. The polypeptide of claim 1 wherein the other genera of bacteria include Escherichia, Serratia, Pasteurella, Proteus, Actinobacillus, and Bordetella.
 9. The polypeptide of claim 7 wherein the other members of the hemolysin family of toxins comprise alpha-hemolysin from Escherichia coli; leukotoxin from Actinobacillus actinomycetemcomitans; leukotoxin from Pasteurella haemolytica; adenylate cyclase from Bordetella pertussis; and adenylate cyclase from Bacillus anthraces.
 10. The polypeptide of claim 7 wherein the other member of the hemolysin family of toxins is alpha-hemolysin from E. coli.
 11. A method of producing an antigen useful in protecting a mammal from infection by N. meningitidis comprising the steps of: (a) preparing an isolated, antigenic polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, or antigenic fragments of such polypeptides; and (b) rendering the polypeptide or fragment non-toxic to mammals.
 12. The method of claim 11 wherein the amino acid sequence is present in a polypeptide found in N. meningitidis.
 13. The method of claim 11 wherein the mammal is a human.
 14. A method of producing a vaccine composition useful in protecting a mammal from infection by N. meningitidis comprising the steps of: (a) preparing an isolated, antigenic polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, or antigenic fragments of such polypeptides; and (b) rendering the polypeptide non-toxic to mammals; and (c) combining the non-toxic polypeptide with a pharmaceutically acceptable carrier.
 15. A method of claim 14 wherein the polypeptide is isolated from N. meningitidis.
 16. The method of claim 14 wherein a the mammal is a human.
 17. A vaccine composition capable of immunizing mammals against infections by N. meningitidis, the vaccine composition comprising: (a) an immunogenic polypeptide that is non-toxic to mammals and comprises a segment having at least fifty amino acid residues, wherein the amino acid sequence is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, or antigenic fragments of such polypeptides; and (b) a pharmaceutically acceptable carrier.
 18. The vaccine composition of claim 17, wherein the polypeptide is present in N. meningitidis.
 19. The vaccine composition of claim 17 wherein the polypeptide is present in outer membranes of N. meningitidis.
 20. The method of claim 17 wherein the mammal is a human.
 21. A method of immunizing mammals against infections by N. meningitidis comprising administering to mammals in need of such protection a vaccine composition that comprises an immunogenic polypeptide in a form that is non-toxic to mammals wherein the polypeptide comprises a segment having at least fifty amino acid residues, and wherein the amino acid sequence of the segment is substantially homologous with the amino acid sequence of a segment of a member of the hemolysin family of toxins, or antigenic fragments of such polypeptides.
 22. The method of claim 21, wherein the amino acid sequence is present in N. meningitidis.
 23. The method of claim 21 wherein the amino acid sequence is present in outer membranes of N. meningitidis.
 24. The method of claim 21 wherein the mammal is a human.
 25. Monoclonal antibodies raised against a polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is present in N. meningitidis, and wherein the amino acid sequence of the segment is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, and antigenic fragments of such polypeptides.
 26. An isolated nucleic acid molecule that encodes a polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is present in N. meningitidis, and wherein the amino acid sequence is different from, but substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, and antigenic fragments of such polypeptides.
 27. A method of detecting the presence of antibodies specific for N. meningitidis in a sample comprising the steps of: (a) preparing an isolated, antigenic polypeptide comprising a segment having at least fifty amino acid residues, wherein the amino acid sequence of the segment is substantially homologous with, the amino acid sequence of a segment of a member of the hemolysin family of toxins, or antigenic fragments of such polypeptides; and (b) determining whether the polypeptide recognizes an antibody in the sample.
 28. The method of claim 27 wherein the polypeptide comprises an amino acid sequence present in N. meningitidis.
 29. An isolated polypeptide comprising a segment having an amino acid sequence present in N. meningitidis wherein the amino acid sequence consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, and antigenic fragments of such polypeptides.
 30. The polypeptide of claim 29 wherein the segment has at least 100 amino acid residues.
 31. The polypeptide of claim 29 wherein the segment has at least 200 amino acid residues.
 32. The polypeptide of claim 29 in essentially pure form.
 33. The polypeptide of claim 29 wherein the antigenic amino acid sequence is immunogenic.
 34. The polypeptide of claim 29 wherein antibodies against the polypeptide cross-react with at least one other member of the hemolysin family of toxins from other genera of bacteria.
 35. The polypeptide of claim 29 wherein the other genera of bacteria include Escherichia, Serratia, Pasteurella, Proteus, Actinobacillus, and Bordetella.
 36. The polypeptide of claim 34 wherein the other members of the hemolysin family of toxins comprise alpha-hemolysin from Escherichia coli; leukotoxin from Actinobacillus actinomycetemcomitans; leukotoxin from Pasteurella haemolytica; adenylate cyclase from Bordetella pertussis; and adenylate cyclase from Bacillus anthracis.
 37. The polypeptide of claim 34 wherein the other member of the hemolysin family of toxins is alpha-hemolysin from E. coli.
 38. A method of producing an antigen useful in protecting a mammal from infection by N. meningitidis comprising the steps of: (a) preparing an isolated polypeptide comprising a segment having an amino acid sequence that consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue; or antigenic fragments of such polypeptides. (b) rendering the polypeptide or fragment non-toxic to mammals.
 39. The method of claim 38 wherein the amino acid sequence is present in a polypeptide found in N. meningitidis.
 40. A method of producing a vaccine composition useful in protecting a mammal from infection by N. meningitidis comprising the steps of: (a) preparing an isolated, antigenic polypeptide comprising a segment having an amino acid sequence that consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or antigenic fragments of such polypeptides; (b) rendering the polypeptide non-toxic to mammals; and (c) combining the non-toxic polypeptide with a pharmaceutically acceptable carrier.
 41. A method according to claim 40 wherein the polypeptide is isolated from N. meningitidis.
 42. A vaccine composition capable of immunizing mammals against infections by N. meningitidis, the vaccine composition comprising: (a) an isolated, immunogenic polypeptide comprising a segment having an amino acid sequence that consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or immunogenic fragments thereof; and (b) a pharmaceutically acceptable carrier.
 43. The vaccine composition of claim 42, wherein the polypeptide is present in N. meningitidis.
 44. The vaccine composition of claim 43 wherein the polypeptide is present in outer membranes of N. meningitidis.
 45. The method of claim 42 wherein the mammal is a human.
 46. A method of immunizing mammals against infections by N. meningitidis comprising administering to mammals in need of such protection a vaccine composition that comprises an isolated, immunogenic polypeptide comprising a segment having an amino acid sequence that consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or immunogenic fragments thereof.
 47. The method of claim 46, wherein the amino acid sequence is present in N. meningitidis.
 48. The method of claim 47 wherein the amino acid sequence is present in outer membranes of N. meningitidis.
 49. The method of claim 46 wherein the mammal is a human.
 50. Monoclonal antibodies raised against an isolated polypeptide comprising a segment having an amino acid sequence present in N. meningitidis wherein the amino acid sequence consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or antigenic fragments of such polypeptides.
 51. A method of treating mammals suffering from diseases caused by infection with N. meningitidis comprising the steps of: (a) preparing antibodies specific to a polypeptide that is a member of the hemolysin family of toxins or an antigenic fragment thereof; and (b) administering the antibodies to a mammal infected with N. meningitidis.
 52. The method of claim 51 wherein the mammal is a human.
 53. The method of claim 51 wherein the antibodies are raised against a polypeptide comprising a segment having an amino acid sequence present in N. meningitidis.
 54. The method of claim 51 wherein the antibodies are monoclonal.
 55. An isolated nucleic acid molecule that encodes a polypeptide comprising a segment having an amino acid sequence present in N. meningitidis wherein the amino acid sequence consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or antigenic fragments of such polypeptides.
 56. A method of detecting the presence of N. meningitidis in a sample comprising the steps of: (a) preparing a probe that recognizes a polypeptide that is a member of the hemolysin family of toxins or a fragment thereof, or a nucleic acid molecule encoding the polypeptide or fragment; and (b) determining whether the probe recognizes N. meningitidis in the sample.
 57. The method of claim 56 wherein the probe is an antibody.
 58. The method of claim 57 wherein the antibody is monoclonal.
 59. The method of claim 56 wherein the probe is a nucleic acid molecule.
 60. The method of claim 56 wherein the polypeptide that is a member of the hemolysin family of toxins or nucleic acid molecule encoding the polypeptide is present in N. meningitidis.
 61. A method of detecting the presence of antibodies specific for N. meningitidis in a sample comprising the steps of: (a) preparing an isolated, antigenic polypeptide comprising a segment having an amino acid sequence that consists of at least three repeats of the nine amino acid hemolysin consensus sequence, the hemolysin consensus sequence consisting of at least four of: L at position 1; G at position 3; G at position 4; G at position 6; N at position 7; D at position 8; and x at positions 2, 5 and 9; wherein x represents any single amino acid residue, or antigenic fragments of such polypeptides; and (b) determining whether the polypeptide recognizes an antibody in the sample.
 62. The method of claim 61 wherein the polypeptide comprises an amino acid sequence present in N. meningitidis. 